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1.
J Econ Entomol ; 105(6): 2045-51, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23356069

ABSTRACT

In the southeastern United States, hunting billbug, Sphenophorus venatus vestitus Chittenden, adults are often observed in turfgrass, but our knowledge of their biology and ecology is limited. Field surveys and experiments were conducted to determine the species composition, life cycle, damaging life stage, and distribution of billbugs within the soil profile in turfgrass in North Carolina. Linear pitfall trapping revealed six species of billbug, with the hunting billbug making up 99.7% of all beetles collected. Data collected from turf plus soil sampling suggest that hunting billbugs have two overlapping generations per year in North Carolina and that they overwinter as both adults and larvae. Field experiments provided evidence that adult hunting billbugs are capable of damaging warm season turfgrasses.


Subject(s)
Coleoptera/growth & development , Herbivory , Poaceae , Animals , Larva , North Carolina , Population Density , Seasons , Soil/parasitology
2.
J Econ Entomol ; 101(5): 1624-32, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18950045

ABSTRACT

Larvae of Phyllophaga spp. (Coleoptera: Scarabaeidae) are important turfgrass pests in many regions of the United States. However, not all of the species associated with turfgrass are known, including species most likely to be of economic concern in Oklahoma turfgrasses, especially Bermuda grass. This study documented the species composition and seasonal occurrence of Phyllophaga associated with high maintenance Bermuda grass turf in Oklahoma over a 2-yr period. In 2005 and 2006, adult Phyllophaga spp. were collected with blacklight traps from selected golf courses throughout Oklahoma Phyllophaga larvae were obtained from Bermuda grass stands at selected sod production facilities adjacent to or near the light traps. We collected 20 species of Phyllophaga beetles in light traps, and nine species of Phyllophaga larvae from turfgrass. Peak flight periods for most species occurred in May and June, but some were captured as early as mid-April and others as late as September. The cytochrome c oxidase I (COI) gene from adults and larvae was amplified using polymerase chain reaction, sequenced, and then used to compare larval DNA against DNA from identified adults. These results confirmed the validity of using COI sequences to identify species of some Phyllophaga larvae. The identifications will aid in optimizing the timing of insecticide applications against Phyllophaga white grubs as discussed.


Subject(s)
Coleoptera/classification , Cynodon/parasitology , Seasons , Animals , Coleoptera/genetics , Coleoptera/growth & development , DNA/chemistry , Larva/classification , Larva/genetics , Larva/physiology , Oklahoma , Phylogeny , Sequence Analysis, DNA
3.
J Mol Evol ; 42(5): 512-24, 1996 May.
Article in English | MEDLINE | ID: mdl-8662003

ABSTRACT

The evolutionary past of intragenic repeats in protein-coding exons of c-, N-, L-, and s-myc-protooncogene subfamilies was elucidated. Apparently these genes evolved by succession of distinct unit events rather than by a steady flow of random point mutations. An evolutionary event probably involved a duplication of the whole gene, which was followed by amplification of progressively shorter oligonucleotide themes and motifs. The repeats were either joined in tandem or one of the copies was transposed and integrated elsewhere within the same exon. In some instances multiple fragments of an amplified theme were integrated at several sites. Direct repeats were found to prevail over inverted ones. By reconstructing the fate of repeats in the course of evolution of vertebrates, the origins of some functional domains could be traced to the initial amplification event. For example, an N-myc-specific domain was created by tandem duplication of a single-copy theme of L-myc exon; at the time of divergence of the c-myc and N-myc, the tandem duplex underwent a new round of duplication followed by transposition of the new copy, thus accounting for the formation of a new domain specific for c-myc. The model proposed here may be regarded as a molecular-level equivalent of the theory of punctuated equilibria.


Subject(s)
Evolution, Molecular , Genes, myc , Multigene Family , Oligonucleotides/genetics , Animals , Base Sequence , Exons/genetics , Gene Frequency , Hominidae/genetics , Humans , Mice , Molecular Sequence Data , Rats , Repetitive Sequences, Nucleic Acid , Vertebrates/genetics
4.
Gene ; 117(2): 233-5, 1992 Aug 15.
Article in English | MEDLINE | ID: mdl-1639269

ABSTRACT

Recombinant baculoviruses expressing the v-myb and c-myb genes in infected insect cells were constructed. The electrophoretic mobilities of their immunoreactive products were the same as those of the authentic Myb proteins from chicken cells. The system provides a convenient source of relatively large amounts of v-Myb or c-Myb for in vitro binding studies.


Subject(s)
Avian Myeloblastosis Virus/genetics , Baculoviridae/genetics , Cloning, Molecular , Proto-Oncogene Proteins/genetics , Retroviridae Proteins, Oncogenic/genetics , Animals , Cell Line , Immunoblotting , Moths/microbiology , Oncogene Proteins v-myb , Plasmids/genetics , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins c-myb , Recombinant Proteins/biosynthesis , Recombinant Proteins/genetics , Restriction Mapping , Retroviridae Proteins, Oncogenic/biosynthesis
5.
Mol Gen Genet ; 214(2): 343-7, 1988 Oct.
Article in English | MEDLINE | ID: mdl-3237210

ABSTRACT

Natural recombinant genomes between several, phenotypically distinct forms of phages kappa and theta were isolated and characterized by DNA restriction fragment mapping and electron microscopic heteroduplex analysis. The phenotypes of the recombinants were correlated with the physical maps of the genomes, and several genetic functions were therefore defined and mapped. All genes necessary for the assembly of infectious virus particles map in a contiguous tract of DNA comprising about 20 kb, or nearly one third of the genome length. No DNA homology occurs within these domains of the two genomes, so that homologous recombination does not take place here and phenotypic mixing of the phages is eo ipso excluded. Other regions of heterology contain regulatory genes responsible for the lytic or temperature character of the phages, and for exclusion of phage kappa by 9.


Subject(s)
Bacillus/genetics , Bacteriophages/genetics , Genes, Fungal , DNA, Viral/ultrastructure , Microscopy, Electron , Nucleic Acid Heteroduplexes/ultrastructure , Recombination, Genetic , Restriction Mapping
6.
Mol Gen Genet ; 205(3): 530-4, 1986 Dec.
Article in English | MEDLINE | ID: mdl-3031430

ABSTRACT

The physical maps of the LP51 and LP52 prophages in lysogenic strains of Bacillus licheniformis were constructed on the basis of data obtained by hybridization of phage DNA probes with Southern blots of restricted DNA of the lysogens. The data were compatible with the Campbell model for chromosomal integration; the attP site was mapped at 58.7-61.8 map units of the genomes of both phages. Identification of prophage-host DNA junction fragments indicated the presence of a unique attB site on the bacterial chromosome; the set of junction fragments in the strain B. licheniformis ATCC 10716 was identical to that of ATCC 11946, but different from ATCC 8187. Both the LP51 and LP52 phages used the same integration sites. Upon reinfection with either phage, the cured strains UM12 and UM18 (i.e. 10716 and 11946 cured of LP52 or LP51, respectively) turned out to be integration deficient. In surface cultures the reinfected bacteria could be maintained in the lysogenic state without, however, integrating the phage genome; when these bacteria were passaged in submerged cultures, several modes of anomalous integration were observed, and the phage segregated into a variety of forms, discernible by virulence and plaque morphology. In liquid cultures of UM12(LP51) or UM12(LP52) lytic forms finally predominated, while most lysogenized UM18 were converted into defective lysogens which contained a defective prophage in a stably integrated form.


Subject(s)
Bacillus/genetics , Bacteriophages/genetics , Genes, Viral , DNA Restriction Enzymes , DNA, Viral/genetics , Lysogeny
7.
Gene ; 41(2-3): 327-9, 1986.
Article in English | MEDLINE | ID: mdl-3710163

ABSTRACT

Employing electron microscopy (EM) of partially denatured DNAs of phages LP52 and theta, distinct denaturation maps were determined and correlated with published restriction and heteroduplex maps. The pattern of early melting regions is similar although the two phages share only 50% nucleotide sequence homology.


Subject(s)
Bacillus/genetics , Bacteriophages/genetics , DNA, Viral , Microscopy, Electron , Nucleic Acid Denaturation , Nucleic Acid Heteroduplexes , Species Specificity
8.
Mol Gen Genet ; 199(3): 476-80, 1985.
Article in English | MEDLINE | ID: mdl-2993798

ABSTRACT

The genomes of the phylogenetically related but morphologically distinct bacteriophages LP52 and theta (theta) were compared by electron microscopic heteroduplex analysis. The heteroduplex maps were aligned with known restriction maps. In the heteroduplices of LP52 DNA (63.8 kb) with the DNA of the lytic phage theta c (65.9 kb) the tracts of homologous DNA cover about 50% of the genome length and are interspaced by four large and ten smaller non-base-paired regions. The largest block of non-homologous DNA (18.9 kb), represents the right-hand end and there is an unmatched piece of DNA at the left-hand end as well. Most of the heterology is due to substitution resulting in the conservation of the total length of DNA; the three insertions/deletions amount to less than 3.2% of the genome length. Heteroduplices between the DNAs of phage LP52 and the temperate phage theta 1 (65.0 kb) resembled those of LP52:theta c except for the absence of minor loops. Heteroduplex theta c:theta 1 displayed about 9% heterology in seven separate loops which coincided with sections of diversity on the restriction maps; 4.8% of theta 1 DNA did not hybridize with either theta c or LP52 DNA.


Subject(s)
Bacillus/genetics , Bacteriophages/genetics , DNA, Viral/genetics , Nucleic Acid Heteroduplexes/genetics , DNA Restriction Enzymes , Microscopy, Electron , Species Specificity
10.
Mol Gen Genet ; 187(1): 138-47, 1982.
Article in English | MEDLINE | ID: mdl-6298569

ABSTRACT

A restriction fragment map of Bacillus licheniformis temperate phage LP 52 DNA (molecular weight 38.5 X 10(6)) was established, using restriction endonucleases BamHI (8 target sites), BglI (10 sites,) BglII (13 sites) and EcoRI (22 sites). The map is linear, with well-defined ends, without any signs of circular permutation. The DNA of a related phage, LP 51, produced identical restriction fragments. At least 62% DNA of LP 52 has been found homologous to the DNA of the recently discovered, morphologically quite dissimilar, phage I, as demonstrated by hybridization of electrophoretically separated restriction fragments of DNA. Under the same conditions, the DNAs of LP 52 and of the morphologically similar Bacillus subtilis phage phi 105 did not cross-hybridize. The homologous regions in the genomes of phages LP 52 and I have been shown to be colinear. Comparison of the cleavage maps of phages LP 52 and I has shown that, within the regions of homology, not a single restriction fragment and few restriction sites have been conserved during divergent evolution. Three major regions of heterology were defined; the longest one, covering the right-hand end of the map (73 +/- 2.75% up to 100% LP 52 genome length) appeared to contain genes coding for structural proteins of the virions; a shorter region at the left-hand end of the map (coordinates zero to 10.3 +/- 3.3% LP 52 genome length) and a very short central region (coordinates 41.8-43.9%) could be identified, the latter apparently containing a regulatory locus responsible for the heteroimmune behavior of the two phages. Recombinants between phages LP 52 and I were isolated. Mapping of recombinant genomes has indicated mutual substitution of allelic pieces of LP 52 and I DNAs upon strict conservation of overall genome length.


Subject(s)
Bacteriophages/genetics , DNA, Recombinant , Genes, Viral , Base Sequence , DNA Restriction Enzymes/metabolism , DNA, Viral/genetics , Hybridization, Genetic , Phenotype
11.
Mol Gen Genet ; 182(1): 125-32, 1981.
Article in English | MEDLINE | ID: mdl-6267429

ABSTRACT

Restriction maps of genomes of the lytic form and diverse temperate mutants of phage theta of Bacillus licheniformis were constructed. Most temperate mutants produced fragmentation patterns identical to that of the parent lytic form, theta c: in other mutants the only detectable change in the map was the deletion of a Bg/II restriction endonuclease site at 46.5% genome length. In the genomes of two other temperate mutants, theta 1 and theta 2, the central part of the genome was replaced by a piece of DNA of equal length, but with a different distribution of restriction sites; the maps of the two mutants failed to reveal any similarity in the location of restriction sites in the inserted DNA. It seems that any alteration comprising the locus around the coordinate 46.5% of the theta c genome, brings about a transition from the lytic to temperate phenotype, indicating the position of a regulatory gene responsible for positive control of phage replication.


Subject(s)
Bacillus/genetics , Bacteriophages/genetics , DNA, Viral/genetics , Chromosome Mapping , DNA Restriction Enzymes/metabolism , Lysogeny , Molecular Weight , Mutation
12.
Biochim Biophys Acta ; 609(1): 40-52, 1980 Aug 26.
Article in English | MEDLINE | ID: mdl-6250614

ABSTRACT

The pattern of the degradation of various double-stranded polyribonucleotides by several ribonucleases (bovine RNAase A and its cross-linked dimer, bovine seminal RNAase, and pike-whale pancreatic RNAase) has been studied as a function of ionic strength and pH. It appears that (1) there is no direct correlation between the secondary structure of double-stranded RNA and its resistance against enzymatic breakdown, i.e., the stability of the secondary structure of double-helical RNA is not the main variable in the process. (2) The acstivity responses of the enzymes examined to changes of ionic strength and pH suggest that enzymic degradation of double-stranded RNA is mainly controlled by ion concentration, and that the process may fall within the phenomena interpreted by the theory of the ionic control of biochemical reactions advanced by Douzou and Maurel (Douzou, P. and Maurel, P. (1977) Proc. Natl. Acad. Sci. U.S.A. 74, 1013--1015). (3) The activity curves of the enzyme studied show, at a given pH, a shift toward higher ionic strengths as a function of the basicity of the enzyme protein. This finding explains the already observed correlation between number and/or density of positive charges of a ribonuclease molecule and its ability to attack double-stranded RNA in 0.15 M sodium chloride/0.015 M sodium citrate (SSC). (4) A careful analysis of the influence of ionic strength and pH on the reaction appears to be necessary in order to characterize a ribonuclease which shows activity towards double-stranded RNAs, and to allow a meaningful comparison between different enzymes capable of attacking these substrates.


Subject(s)
RNA, Double-Stranded/metabolism , Endonucleases , Hydrogen-Ion Concentration , Poly A/metabolism , Poly C/metabolism , Poly U/metabolism , Ribonuclease, Pancreatic , Ribonucleases
14.
Folia Biol (Praha) ; 26(1): 42-6, 1980.
Article in English | MEDLINE | ID: mdl-7364131

ABSTRACT

A parallel testing of antibodies to double-stranded ribonucleic acid in 80 sera from patients with systemic lupus erythematosus by the membrane binding method using natural 3H-dsRNA preparation and synthetic 125I-poly I. poly C preparation revealed a good correlation (r = +0.81). In a selected set of patients with SLE we observed a slight tendency to preferential binding of the natural preparation and a lower frequency of anti-dsRNA antibodies when compared to that reported by other investigators. The presence of anti-dsRNA did not correlate with the presence of anti-dsDNA.


Subject(s)
Antibodies/analysis , Lupus Erythematosus, Systemic/blood , Polyribonucleotides/immunology , RNA, Double-Stranded/immunology , DNA/immunology , Humans , Poly C/immunology , Poly I/immunology
15.
Acta Virol ; 23(6): 481-8, 1979 Nov.
Article in English | MEDLINE | ID: mdl-94768

ABSTRACT

The administration of sonicated fractions of f2 phage polyribonucleotides caused an increased weight loss and deterioration of the clinical state in female NZB mice. Discontinuance of the treatment resulted in an improvement of both the clinical state and the genetically determined autoimmune disorders of these mice. Some potential explanations of this effect are discussed.


Subject(s)
Autoimmune Diseases/drug therapy , Polyribonucleotides/therapeutic use , Animals , Antibodies/analysis , Autoimmune Diseases/immunology , Autoimmune Diseases/metabolism , Complement C3/analysis , DNA/immunology , Female , Interferons/biosynthesis , Male , Mice , Mice, Inbred NZB , Molecular Weight , Poly I-C/therapeutic use , RNA, Double-Stranded/immunology , RNA, Double-Stranded/therapeutic use , Sonication
18.
Czech Med ; 2(3): 134-40, 1979.
Article in English | MEDLINE | ID: mdl-535500

ABSTRACT

Prolonged repeated analyses of sera from 98 patients with systemic lupus erythematosus (SLE) and 76 patients with similar diffuse diseases of connective tissue by a radioisotope membrane binding method for the assessment of antibodies against double-stranded ribonucleic acid (anti-ds-RNA) revealed that these antibodies are most frequently encountered in patients with the evolutive form of SLE (53%), but also in approximately one fifth of patients with non- evolutive SLE and in patients with similar diffuse diseases of connective tissue. Anti-ds-RNA are not linked with stages of clinical activity; their occurrence is on the whole independent on the occurence of antibodies against ds-DNA and nuclear ribonucleoprotein. There is a very close association with the incidence of antibodies against denatured DNA and a substantially small association with antibodies against acid nuclear antigen (Sm). The occurrence of anti-ds-RNA is a favourable prognostic sign, as in the majority of patients who had such antibodies at any time in their serum, later the disease can be suppressed by treatment, while patients who never had anti-ds-RNA in serum remain for a long time in the active stage of the disease.


Subject(s)
Autoantibodies/analysis , Connective Tissue Diseases/immunology , Lupus Erythematosus, Systemic/immunology , RNA, Double-Stranded/immunology , DNA/immunology , Humans
19.
Nucleic Acids Res ; 6(1): 57-70, 1979 Jan.
Article in English | MEDLINE | ID: mdl-424300

ABSTRACT

Restriction fragment patterns of G+C-rich satellites of sheep and goat DNA were compared. The 1,712 g/cm3 satellites of both species appear homologous, consisting of repeats 760 base pairs long and showing coincidence of position of primary+ EcoRI, BamHI and most BspRI restriction target sites. The EcoRI and BamHI endonucleases produce mostly monomers of the repeating unit, while oligomers prevail in the A1uI and Bg1II digests. Species-specific differences in the frequency, position and mode of distribution of secondary+ restriction target sites for EcoRI, Bg1II and A1uI were observed. Unlike the 1,712 g/cm3 satellites, the 1,723 g/cm3 component of sheep DNA and the 1,719 g/cm3 material from goat DNA appear species--specific, since no homologous material could ever be detected in the DNA of the other species.


Subject(s)
Cytosine/analysis , DNA, Satellite , DNA , Guanine/analysis , Animals , Cell Nucleus/analysis , DNA Restriction Enzymes , Goats , Liver/analysis , Nucleic Acid Renaturation , Sheep , Species Specificity
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